Manufacture of steel.



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WELFLIAM n. wemrnn, ornnw roux, n. v.

No Drawing.

To all whom it may concern Be it known that I, WILLIAM R. Na um, of the city, county, and State of New .1 ork,

have invented a new and useful Improve ,ment in the Manufacture of Steel, of which the following is a specification.

My invention relates to the manufacture of steel by the use of the electric furnace succeeding the Bessemer converter or open hearth furnace: and is designed to reduce the expense of manufacture and make the steel more uniform and better in quality.

'I In the ordinarymanufacture of steel the manganese contained in the pig iron is almost Wholly lost through oxidation in the Bessemer converter or open hearth furnace. In such practice it is necessary to add inanganese. or an alloy thereof, to obtain the desired quality of steel.

My invention is designed to Wholly or largely a void the addition of manganese tothe steel: and to utilize the larger portion be repla of the manganese c ntained in the pig iron. This manganese performs a very useful function in the electric furnace, owing to its effect on the oxidized iron of the bath. *ieretofore. however. it has been considered necessary to re uce the analogynesgto a small proportion of the original amount, in the Bessemer or open hearth heat; and t 1 ch is lost must l have found hat when Bessemer con verter or open hearth furnace is used in corn nection with an electric furnace I can obtain important advantages by stopping the heat short Off the. usual point. and at a stage Where a large part, and preferably the major portion of the manganese retained in the bath. 1 have also found that where a series of converters or open hearth furnaces is used, variations the manganese con tent of le nartly reduced may he equalized by suppl a. a mixer of large capacity between the converters or open hearth furnaces and the electric furnace. This raiser is adapted to hold a. number of heats or charges at one time; and provides a constant and steady supply of metal to the electric furnace, While equalizing the percentage of uietalloids in the metal taken to the electric furnaces. lit is "-lso of a lvantage giving heats of more uniform. duration and afi'orting a more uniform. product from the electric furnaces. in ad.- dition to this mixer between the steel mah Specification of Letters Patent.

Patented 0 4st. 5, 1915.

ing apparatus and the electric furnaces, I also preferably provide an additional receiver or ladle on the casting side of the electric furnaces, and which is adapted. to hold charges from a numberof these furnaces at one time; From this receptacle,

taken to the molds.

orlarge ladle, on the casting side of the electric furnaces, the metal may be tapped or poured into the ladles, by which it is This additional receiver will aid in equalizing the variations in the product of the various electric furnaces, thus insuring amore uniform product. The mixer and the receiver may be heated either electrically or by gas, or any other desirable Way.

In carrying out my process, therefore, 1' stop the heat of the Bessemer converter or openhearth furnace beforeit is carried to the usual point, and while a large and pref erably a major percentage of the contained .inanganese is present'in the metal, the manized in manganese content and will carry a larger portion of the manganese that is new obtained. In the electric furnace the metal is deoxidized, largely through the action of manganese. I, therefore, Wholly or largely avoid the addition of manganese to the electric furnace and utilize that contained in the original pig iron for this purpose. In my preferred practice I then tap or pour the charges from the electric furnace and feed them into the large ladle or receiver Where the metal is further equalized, and from which it is tapped or poured into smaller ladies and poured into the molds.

The advantages of my invention result:

List-from the retention of the manganese,

and the open hearth may be either basic or acid; the electric furnace is preferably basic lined; but apparatus of various kinds may be used, and variations maybe made in the steps of my process, without departing from my invention.

I claim:

1. In the manufacture of steel, the steps comprising treating molten iron containing a percentage of manganese in a Bessemer converter or open hearth furnace, stopping the treatment While the percentage of manganese is relatively l'iigh, transferring the heated metal to a basic-lined electric furnace and treating it therein.

2. In the manufacture of steel, the steps comprising treating molten iron containing a percentage of manganese in a Bessemer converter or open hearth furnace to remove at least a part of the silicon and carbon, then before the elimination of a considerable percentage of the manganese transferrin Y the metal to a basic-lined electric furnace and treating it therein.

3. In the manufacture of steel, the steps comprising treating molteniron containing a percentage of manganese in an acid-lined Bessemer converter or an open hearth furnace for the removal of at least a part of the silicon and carbon and retention of a portion of the manganese, and after the elimination of the greater percentage of silicon and carbon and the removal of a less percentage of manganese, transferring the metal to a basic-lined electric furnace and treating it therein.

i. In the manufacture of steel, the steps comprising treating molten iron containing a percentage of manganese, in a Bessemer converter or open hearth furnace, until the manganese is reduced to not lower than .10

per cent, and then transferring tlre metal to a basic-lined electric furnace it therein.

5. In the manufacture of steel, the steps comprising treating molten iron containing a percentage of manganese in an acid-lined Bessemer converter or open hearth furnace and treating for the removal of at least a part of the silicon and carbon and retention of a portion of the manganese, and after the elimination of the greater percentage of silicon and carbon and the removal of a less per centage of manganese transferring the metal to a mixer wherein the percentages of manganese are. rendered more uniform, and thereafter transferring the metal to and treating it in a basic-lined electric furnace.

6. In the manufacture of steel, the steps comprising treating the molten iron containing a percentage of manganese in an aci ,l.-line l Bessemer converter or an open hearth furnace, t'ansferring the metal be fore the completion of the heat to a metal mixer wherein the metals of uniform heats are rendered uniform, then transferring the metal to and treating it in an electric furnace, and thereafter transferring it to'a receiver whereby any variations in the content of the charges from the electric furnace are compensated for.

7. In the manufacture of steel, the steps con'iprising treating molten iron in a Bessemer converter or open hearth furnace, stopping the heat while the manganese pcrcentage is relatively large, then treating the resulting metal in a plurality of electric fur naces, and mixing the steel taken from the plurality of such electric furnaces. I

8. Iii the manufacture of steel, the steps comprising partially refining molten iron in a plurality of combustion furnaces, transferring the metal from said furnaces to a mixer, transferring successive charges of metal from the mixer to a series of electric furnaces, purifying the metal in said electric furnaces, and then feeding the finished steel'fron said furnaces to a mixer and Withdrawing the mixed metal from said mixer.

In testimony whereof, l have hereunto set my hand.

\YILLI AM R. WALKER Witnesses: I

VILLIAM Y. (lonLnrT, CLARENCE D. KERR. 

